A conventional treadmill generally includes a base, a frame which has one end pivotably connected to the base and an endless belt is connected to the frame. The endless belt can also be driven by a motor so that the users set desired speed of the belt to exercise.
In order to save the space occupied by the treadmill, some treadmills are equipped with a folding device which allows the frame to be pivoted relative to the base. U.S. Pat. No. 6,527,679 discloses a folding mechanism which uses a motor and a threaded rod which is driven by the motor and a connection member pivotably connected to the frame is movably mounted to the threaded rod so that when the threaded rod is rotated by the motor, the connection member pivots the frame. It is noted that the frame is pivotably connected to the base at one point on each of the two sides of the base so that there requires a large angle to pivot the frame relative to the base. Further, another prior art shown in FIG. 8, discloses a similar folding mechanism which is located at the middle portion 51 of the frame 50 so that a less effort is required to pivot the frame 50. However, in order to accommodate the folding mechanism, the frame 50 has to be located at a higher position which makes the treadmill unstable.
The present invention intends to provide a folding device which provides two separated pivotal points on each of two sides of the base for connection with the frame so that the frame can be easily folded relative to the base.